I would say just go slow and steady and buy a good blending brush. I have a Mac eyeshadow brush and I blend back and forth until it’s how I like it

I dont really know that I have any tricks as such.
I think it just takes practice and finding what suits you best.
I dont really follow any rules when it comes to eye makeup. I do my own thing.

I do the three colour method. Lightest colour at the inner eye, a little darker in the middle, darkest at the other end and blend that into the crease, then fade out. Add a little metallic on top if you’re feeling it. I use to experiment when my husband worked night shifts before a shower to hone in on what looked good on me